The overall objective of this work is to produce and characterize monoclonal antibodies directed to nonsmall cell lung carcinoma and then use these monoclonal antibodies to treat lung carcinomas established in athymic mice. During the past 12 months, we have thoroughly characterized an existing panel of monoclonal antibodies and selected two, KS1/4 and KS1/9, for further studies. Additionally, we have produced more monoclonal antibodies directed to lung squamous carcinoma and a metastasized adenocarcinoma. In the next year, we plan to: (1)\test MoAb KS1/4 and KS1/9 as to their ability to kill established tumors in athymic mice; (2)\biochemically characterize the antigens with which KS1/4 and KS1/9 are reactive. This will involve HPLC isolation, limited amino acid sequence analysis, and TLC antibody overlay to identify the KS1/9 antigen; (3)\assess the density of KS1/4 and KS1/9 antigens on a panel of tumor cells by FACS analysis; (4)\continue testing MoAb KS1/4 and KS1/9 in immunotherapeutic agents for lung tumors established in athymic mice; and (5)\characterize the new monoclonal antibodies to squamous carcinoma by immunoperoxidase staining of fresh frozen and paraffin-embedded normal and tumor tissues. (AB)